ERG Mode spikes

I recently upgraded from a wheel on trainer (Elite Novo) to a direct drive trainer (Elite Zumo), on my old trainer in ERG mode the power matching to the target was exactly on point all the way though the wrok out, with my new trainer the power is up and down by 30 Watts or more at time at some points, I can feel the resistance changes so I no it is definitely being controlled by the software but it looks like I’m riding in ERG mode (spiking up and down around the target power).

Is this what all direct drive trainers are like or do I have a faulty one?

I haven’t changed any settings in trainerroad software and I’m using the same set up, I have tried it with ANT+ and Bluetooth and it is a bit smoother with Bluetooth but it makes the rides a lot more difficult, fluctuating from 230 to 290 Watts when I’m supposed to be doing 260 is really annoying and hard to maintain.

Hey Cooke!

Some trainers such as the Wahoo Kickr track the Target Power more closely than other trainers, but seeing some variation is totally normal depending on your specific model. +/- 30 watts is certainly a bit dramatic, but see if you can decrease that variation by focusing on smoothing your pedal stroke as much as possible.

You may also want to apply Power Smoothing within the TrainerRoad app to apply a rolling average to the data for a more useful power reading. 3 seconds is a good place to start, and you can increase from there if you want more smoothing, or decrease it if you want a faster response.

Give that a shot, and if you still feel that your trainer is not behaving correctly, reach out to our Support Team at and they can take a closer look.

my power smoothing is set to 3 seconds already and that is what it was at before, i will try increasing it to 5 seconds and see if it is any better.

i think my cadence is about as smooth as it can be to be honest, my preferred cadence is 93rpm and i can hold that easily without focusing but i did actively focus to try and keep it from effecting my power but it didn’t help, in the 15 minute efforts i was doing my cadence didn’t fluctuate from 92 or 93 apart from when i stood for a minute and the power was still fluctuating.

you can see the difference when comparing these screenshots

What gear are you riding in? If big ring, small cog, this can lead to bigger fluctuations. Try small ring, middle of cassette and see if that helps.

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50 on the front and the middle of the cassette on the back, my set up is exactly the same as it was with my old trainer.

The bottom chart is artificial. The flat line is target power, not actual.

The top chart does not look unreasonable, especially if you do not have any power smoothing enabled. Try small ring, middle cassette. That may reduce the fluctuations.

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For clarity, the Power Smoothing setting in TR only affects the 3-digit live Power display value. It does NOT affect the graph in any way.


I knew smoothing just effected the display, and not actual behavior of the trainer. But I assumed the display included the chart and the power digit display. Thx for clarifying it’s just the power digits.

Here’s a 5 min snapshot from a recent workout. I have an Elite Direto. You can see power bounces around in this chart also.

Your 5min snapshot looks pretty normal to me

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Agree. The pic from the OP does not look too dissimilar.

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This is not excessively variable behavior. In fact, this is exactly what I would expect from a majority of the trainers on the market. There a few trainers that appear smoother, but the reality is that no one’s pedal stroke is perfect and will naturally experience some variation. Your trainer is simply showing that variation with a higher level of accuracy :+1:.


I had exactly the same experience moving from wheel on to the Zumo:

Maybe this is normal and I’m just used to having it easy with a lower quality trainer, it just doesn’t feel right because u can really feel the power going up and down like a wave when my cadence is really smooth, it feels like the trainer is fighting me like inexperienced people do when they try erg mode for the first time, like I have my head down pedalling constantly and then I feel the resistance increase so I look up at the screen and I see the power go from around 260 to about 280 or more and then after a few seconds I feel it drop off again and it feels really easy and it then shows I’m doing around 230 Watts.

  1. Are you certain that you don’t have another app/device connected to the trainer?

    • If you do, the two devices can “fight” for control and lead to yo-yo resistance changes similar to what you describe. Usually the difference is quite dramatic, but it could be related.
  2. Are you certain that you are maintaining a steady cadence?

    • Even slight variation can lead to constant resistance changes with some trainers. This is made even worse when using Power Match, since it adds to the overall process and can lead to more variation.

Nothing else should be connected to the trainer beside my computer because the only other thing that has paired to it was my phone to update the firmware and I disabled the Bluetooth on it.

I’m confident my cadence is smooth and u can see from the screenshot I am very consistent with my cadence and always naturally drift to 93 rpm.

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Hmm, that is peculiar. If you haven’t already, I would recommend reaching out to our Support Team at so that they can look at your logs and see if they can shine some light on the situation.

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I had exactly the same when i moved from my wheel elite qubo to my Tacx flux. From what i’ve read the qubo was not as accurate which lead to all my graphs being perfectly smooth ( almost like it was not reporting a change within +/- 5 watts )

I had a similar problem with my kickr and 4iiii with powermatch.

Changing to small cog on front and large on rear (36/28) solved this problem for me, definitely worth a try.